EPIDERMAL GROWTH FACTOR RECEPTOR MUTATIONS AND PROGNOSIS IN NON-SMALL CELL LUNG CANCER CASES IN BRUNEI DARUSSALAM.

Chie Hui LEONG¹, Suwarni DIAH¹, Lin NAING¹, Pemasiri Upali TELISINGHE², Shir Kiong LU³

¹Pengiran Anak Puteri Rashidah Sa’adatul Bolkiah Institute of Health Sciences,

Universiti Brunei Darussalam, Jalan Tungku Link, BE1410, Gadong, Brunei Darussalam.

²Department of Histopathology, Raja Isteri Pengiran Anak Saleha Hospital, Bandar Seri Begawan BA1710, Brunei Darussalam.

³The Brunei Cancer Centre (TBCC), Jerudong Park, BE3122, Brunei Muara, Brunei

Darussalam.

ABSTRACT

Introduction: This study characterizes Epidermal Growth Factor Receptor (EGFR) mutations in patients with non-small cell lung cancer (NSCLC) in Brunei Darussalam, and assesses the prognostic roles of EGFR mutations and survival benefit of EGFR tyrosine-kinase inhibitors (TKIs) therapy. Materials and Methods:  Data from The Brunei Cancer Centre was used for retrospective analysis of clinicopathological characteristics on NSCLC patients diagnosed from 2010 to 2017. The progression-free survival (PFS) of patients on EGFR TKI and overall survival (OS) of patients with EGFR-mutations and EGFR wild types were compared using survival analysis. Results: Result of NSCLC EGFR mutation analysis was evaluable in 71 cases, of which 40 cases were classified as EGFR wild type and 31 cases of EGFR mutations, indicating the prevalence of EGFR mutation of 43.7%, with most cases found in females (22, 71.0%) and non-smokers (20, 64.5%). Mean age of patients with NSCLC EGFR mutation was 63.3 years. Exon 21 point mutation (L858R) (15, 50.0%) was most prevalent, followed by Exon 19 deletion (12, 40.0%). Male gender (OR=0.24, P=0.022) and Stage IV disease (OR=0.24, P=0.040) tend to be significantly less associated with EGFR mutation. A total of 65.2% of patients who received EGFR TKI therapy have achieved an objective response rate. The median PFS for all patients treated with TKI was seven months. The median PFS of patients treated with first line TKI and initial chemotherapy were eight and six months (P=0.045) respectively. EGFR-mutated patients also showed improved OS compared to wild type (29 vs 17 months) although this did not achieved statistical significance (p=0.2). Conclusion: The observed improved median PFS and OS in our NSCLC EGFR-mutation patients on personalised EGFR TKI therapy supports the routine analysis for EGFR mutations in all patients diagnosed with NSCLC to identify individuals who may benefit from EGFR TKI therapy.

Keywords: Non-Small Cell Lung Cancer, Epidermal Growth Factor Receptor, Mutations, EGFR Thyrosine Kinase Inhibitor, Progression Free Survival.

Corresponding author: Shir Kiong Lu, The Brunei Cancer Centre (TBCC), Jerudong Park, BE3122, Brunei Muara, Brunei Darussalam.

Telephone no.: +673 7170228

Email: dr.lu@jpmc.com.bn

Brunei Int Med J. 2019;15:44-52